The proposed regulations, considered by state officials to be the most stringent in the country, were announced on Friday in response to a law that Gov. Jerry Brown signed in September.
Companies would also be required to disclose the chemicals used and acquire permits before they start hydraulic fracturing, or fracking. The rules go into effect in 2015, but there will be emergency regulations that companies would have to comply with beginning in January.
Fracking involves pumping huge amounts of water, sand and chemicals into deep rock formations to release oil or natural gas. Other well stimulation techniques use acid to break apart oil-rich formations. While the state oversees oil wells, there have not been specific rules for fracking, which has been going on for decades in California.
Some environmentalists contend the proposed rules don't go far enough and want a fracking ban until regulators can study whether there are risks to public health.
"We want a timeout," said Kathryn Phillips, state director of the Sierra Club told the Los Angeles Times in Saturday's editions.
"At best, these regulations can be described as a mixed bag," she said. "At worst, they provide another example of an agency's continued deference to a regulated entity, even at the expense of public health and the environment."
Other environmentalists said some oversight is better than none.
"There are some good provisions from our very preliminary review," Bill Allayaud of the Environmental Working Group told the newspaper.
Fracking supporters said the rules provide a framework to explore the Monterey Shale, vast formation that extends from California's Central Valley farmlands to offshore and could ultimately comprise two-thirds of the nation's shale oil reserves.
"These regulations are extensive but strike the right balance," Catherine Reheis-Boyd, president of the Western States Petroleum Association, told the Times.
Under the draft rules, state environmental officials will team with air quality regulators and regional water boards to track potential problems after a job. Wells would also be monitored before and after fracking and some of the chemicals used to stimulate wells would be posted online.
State officials will hold a 60-day public comment period with hearings scheduled in several cities around the same.
